Jerome d'Ambrosio says he is not setting himself any targets from the Italian Grand Prix weekend because has nothing to reference himself against.

Replacing the suspended Romain Grosjean for this race, d'Ambrosio's only previous experience in the Lotus E20 came at the Mugello test in May. As a result, d'Ambrosio says he doesn't have enough information to set himself a realistic target for this weekend, but will focus on working well with his team of engineers.

"I think it's very difficult, simply because I don't have much information to set myself a position target or anything," d'Ambrosio said. "I really want to stay focused on what I can do, the job with the engineers in the car, stay focused on that. Once that is done correctly we can go for something on Sunday but only if I stay focused on my job so this is what I will try to do."

Having only been confirmed this week, D'Ambrosio insists he hasn't been overly thinking his race debut for Lotus as he hasn't had time to dwell on the opportunity.

"Obviously it's been short notice - Monday really - so a bit of hectic week for me; back at the factory getting stuff done as much as I could before here to get really prepared as best as I can. I haven't had time to think about anything really, just really getting things done and that's it."

D'Ambrosio does insist, however, that he is fully prepared for a full race weekend despite not completing one since Brazil 2011.

"As a third driver, that's part of the job. You have to keep preparing, keep fit and everything. So that's not been easy ... but I did everything with the engineering meetings and everything trying to keep up to date as much as I could and use every tool that I had in my hand to be as prepared as I can if something like this happened."